topic Unexpected Behavior when Creating or Editing Motion limits in Fusion Support Forum

Unexpected Behavior when Creating or Editing Motion limits

ccox182VRDT — Wed, 05 Jun 2024 22:36:09 GMT

I am attempting to create (or edit) this slider joint with a minimum position of 0mm, a maximum position of -3mm, and a rest of 0mm. Whenever I enter the number for one of the values, the other two change automatically like they are linked, but I see no option to disable linking, and honestly can't think why that would be useful. I am new to making motion joints in fusion, so I'm not sure if this is a bug or if I'm missing something.

I have noticed the same behavior with revolute joints, but was able to get past it by spamming values until they stopped updating themselves. I have also had this issue on two different computers. The issue seems to only occur with negative values, entering positive numbers works as expected (?)

See attached video for example

(view in My Videos)

Re: Unexpected Behavior when Creating or Editing Motion limits

jhackney1972 — Wed, 05 Jun 2024 22:52:28 GMT

When entering values in the Motion Link Dialog, you MUST always have the smallest "mathematical" number in the Minimum field. Even if you think that your maximum movement is the larger number, if it is negative it is the smaller value. For example, you want the maximum movement to be -5 and the minimum -1, the -5 value MUST be entered into the Minimum field. This is why it seems linked to you.

Re: Unexpected Behavior when Creating or Editing Motion limits

jeff_strater — Wed, 05 Jun 2024 22:55:02 GMT

I think that Maximum always has to be bigger than Minimum (not in an absolute value sense, in a "number line" sense - Max must be to the right of Min). When you try to set Min to -0.5, and Max to -3, that violates this restriction. Try just reversing the values: Min of -3, Max of -0.5

Re: Unexpected Behavior when Creating or Editing Motion limits

ccox182VRDT — Wed, 05 Jun 2024 23:29:37 GMT

Thank you John and @jeff_strater

That's a bit counterintutive but I understand why it is the way it is. Appreciate the quick help!